Wound healing begins almost immediately after injury, requiring the coordinated response by a variety of cells and the regulation of degradative and regenerative steps. The complexity of wound healing processes often leads to slow, inappropriate or lack of healing, often with serious medical consequences.
The extracellular matrix of mammalian tissue contains proteins known to support the attachment and promote the migration and differentiation of a wide variety of cells, such as fibronectin, vitronectin, collagens and laminin. When tissue is cut, burned or abraded, the extracellular matrix may be separated or lost. The matrix must be replaced before the wound can be completely repaired.
Accordingly, during wound healing, tissue is replaced by migration of cells into the wound and the subsequent synthesis of extracellular matrix by these cells. Typically, tissue structure and strength are derived by interactions of cells with the extracellular matrix, which is mediated by proteins such as fibronectin, vitronectin, collagen, laminin, etc. that are found in the matrix. The extracellular matrix, in addition to providing a scaffold for cell migration and attachment, also directs cell proliferation and differentiation.
Many analogues of extracellular matrix have been developed to promote wound healing (e.g., Dickerson et al., U.S. Pat. No. 5,677,276; Pierschbacher et al., U.S. Pat. No. 5,955,578; Clark et al., U.S. Pat. No. 6,194,378; Vuori et al., U.S. Pat. No. 5,677,276; McPhee et al., U.S. Pat. No. 6,197,325; Bellamkonda et al., U.S. Pat. No. 6,156,572; Bellamkonda et al., U.S. Pat. No. 5,834,029 and references contained therein). However, novel, optimized biomaterials that lead to rapid and complete wound healing by providing a scaffold for cell migration and attachment, binding or acting as a reservoir for endogenous growth factors are still needed. Also needed are biomaterials that are capable of directing cell proliferation and differentiation.